This proposed research builds on the work of the Fels Longitudinal Study, a unique database that incorporates new data with that accumulated since the study began in 1929. The Fels Longitudinal Study is the world's largest and longest continuous serial study of growth, body composition and risk factors for adult chronic disease in normal individuals. Our long-term study goals are to identify the health effects of the amount and distribution of body composition components (e.g., adipose tissue, fat-free mass); to gain a better understanding of the influences that predispose individuals as children and/or adults to develop overweight/obesity, cardiovascular disease, and other diseases of aging; and to demonstrate the importance of new assessment methods and statistical approaches to describe these relationships better. There are two general aims, each encompassing a set of specific hypotheses focused on the analysis of serial data: l) to use long-term serial data collected throughout the life span to determine the nature of relationships among patterns of change in body composition, systemic inflammatory factors, adipose tissue-derived hormones, and other risk factors for common complex diseases (e.g., cardiovascular disease and obesity); and 2) to examine the effect of childhood changes in body composition on health outcomes in adulthood. Types of questions to be addressed include: Are changes in body composition related to concurrent or previous levels or patterns of change in maturity, physical activity, or other risk factors for cardiovascular disease (e.g., inflammatory markers, blood pressure, lipids, or insulin resistance)? Are patterns of change in risk factors related to adipose tissue distribution? What are the relationships between the age at onset of persistent overweight/obesity and later levels of risk factors for cardiovascular disease? We will continue to quantify body composition and to evaluate specific components related to adiposity, inflammation, and other risk factors for diseases (e.g., cardiovascular disease and diabetes). Continued investigation into the nature of changes in, and relationships among, these variables using new and existing long-term serial data will help to clarify the onset of, and risk factors for, chronic disease from childhood to early old age. Accordingly, innovative analytical approaches will be used in the various analyses.